2 # For a description of the syntax of this configuration file,
3 # see Documentation/kbuild/kconfig-language.txt.
5 # Note: ISA is disabled and will hopefully never be enabled.
6 # If you managed to buy an ISA x86-64 box you'll have to fix all the
7 # ISA drivers you need yourself.
10 mainmenu "Linux Kernel Configuration"
16 Port to the x86-64 architecture. x86-64 is a 64-bit extension to the
17 classical 32-bit x86 architecture. For details see
18 <http://www.x86-64.org/>.
27 config SEMAPHORE_SLEEPERS
41 config RWSEM_GENERIC_SPINLOCK
45 config RWSEM_XCHGADD_ALGORITHM
48 config GENERIC_CALIBRATE_DELAY
60 config GENERIC_ISA_DMA
68 config ARCH_MAY_HAVE_PC_FDC
79 menu "Processor type and features"
82 prompt "Processor family"
86 bool "AMD-Opteron/Athlon64"
88 Optimize for AMD Opteron/Athlon64/Hammer/K8 CPUs.
93 Optimize for Intel Pentium 4 and Xeon CPUs with Intel
94 Extended Memory 64 Technology(EM64T). For details see
95 <http://www.intel.com/technology/64bitextensions/>.
105 # Define implied options from the CPU selection here
107 config X86_L1_CACHE_BYTES
109 default "128" if GENERIC_CPU || MPSC
112 config X86_L1_CACHE_SHIFT
114 default "7" if GENERIC_CPU || MPSC
126 tristate "/dev/cpu/microcode - Intel CPU microcode support"
128 If you say Y here the 'File systems' section, you will be
129 able to update the microcode on Intel processors. You will
130 obviously need the actual microcode binary data itself which is
131 not shipped with the Linux kernel.
133 For latest news and information on obtaining all the required
134 ingredients for this driver, check:
135 <http://www.urbanmyth.org/microcode/>.
137 To compile this driver as a module, choose M here: the
138 module will be called microcode.
139 If you use modprobe or kmod you may also want to add the line
140 'alias char-major-10-184 microcode' to your /etc/modules.conf file.
143 tristate "/dev/cpu/*/msr - Model-specific register support"
145 This device gives privileged processes access to the x86
146 Model-Specific Registers (MSRs). It is a character device with
147 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
148 MSR accesses are directed to a specific CPU on multi-processor
152 tristate "/dev/cpu/*/cpuid - CPU information support"
154 This device gives processes access to the x86 CPUID instruction to
155 be executed on a specific processor. It is a character device
156 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
161 depends on SMP && !MK8
164 config MATH_EMULATION
177 config X86_LOCAL_APIC
182 bool "MTRR (Memory Type Range Register) support"
184 On Intel P6 family processors (Pentium Pro, Pentium II and later)
185 the Memory Type Range Registers (MTRRs) may be used to control
186 processor access to memory ranges. This is most useful if you have
187 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
188 allows bus write transfers to be combined into a larger transfer
189 before bursting over the PCI/AGP bus. This can increase performance
190 of image write operations 2.5 times or more. Saying Y here creates a
191 /proc/mtrr file which may be used to manipulate your processor's
192 MTRRs. Typically the X server should use this.
194 This code has a reasonably generic interface so that similar
195 control registers on other processors can be easily supported
198 Saying Y here also fixes a problem with buggy SMP BIOSes which only
199 set the MTRRs for the boot CPU and not for the secondary CPUs. This
200 can lead to all sorts of problems, so it's good to say Y here.
202 Just say Y here, all x86-64 machines support MTRRs.
204 See <file:Documentation/mtrr.txt> for more information.
207 bool "Symmetric multi-processing support"
209 This enables support for systems with more than one CPU. If you have
210 a system with only one CPU, like most personal computers, say N. If
211 you have a system with more than one CPU, say Y.
213 If you say N here, the kernel will run on single and multiprocessor
214 machines, but will use only one CPU of a multiprocessor machine. If
215 you say Y here, the kernel will run on many, but not all,
216 singleprocessor machines. On a singleprocessor machine, the kernel
217 will run faster if you say N here.
219 If you don't know what to do here, say N.
222 bool "SMT (Hyperthreading) scheduler support"
226 SMT scheduler support improves the CPU scheduler's decision making
227 when dealing with Intel Pentium 4 chips with HyperThreading at a
228 cost of slightly increased overhead in some places. If unsure say
231 source "kernel/Kconfig.preempt"
234 bool "Non Uniform Memory Access (NUMA) Support"
237 Enable NUMA (Non Uniform Memory Access) support. The kernel
238 will try to allocate memory used by a CPU on the local memory
239 controller of the CPU and add some more NUMA awareness to the kernel.
240 This code is recommended on all multiprocessor Opteron systems.
241 If the system is EM64T, you should say N unless your system is EM64T
245 bool "Old style AMD Opteron NUMA detection"
249 Enable K8 NUMA node topology detection. You should say Y here if
250 you have a multi processor AMD K8 system. This uses an old
251 method to read the NUMA configurtion directly from the builtin
252 Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
253 instead, which also takes priority if both are compiled in.
255 # Dummy CONFIG option to select ACPI_NUMA from drivers/acpi/Kconfig.
257 config X86_64_ACPI_NUMA
258 bool "ACPI NUMA detection"
264 Enable ACPI SRAT based node topology detection.
267 bool "NUMA emulation"
270 Enable NUMA emulation. A flat machine will be split
271 into virtual nodes when booted with "numa=fake=N", where N is the
272 number of nodes. This is only useful for debugging.
274 config ARCH_DISCONTIGMEM_ENABLE
280 config ARCH_DISCONTIGMEM_ENABLE
284 config ARCH_DISCONTIGMEM_DEFAULT
288 config ARCH_SPARSEMEM_ENABLE
292 config ARCH_FLATMEM_ENABLE
298 config HAVE_ARCH_EARLY_PFN_TO_NID
302 int "Maximum number of CPUs (2-256)"
307 This allows you to specify the maximum number of CPUs which this
308 kernel will support. Current maximum is 256 CPUs due to
309 APIC addressing limits. Less depending on the hardware.
311 This is purely to save memory - each supported CPU requires
312 memory in the static kernel configuration.
315 bool "Support for hot-pluggable CPUs (EXPERIMENTAL)"
316 depends on SMP && HOTPLUG && EXPERIMENTAL
318 Say Y here to experiment with turning CPUs off and on. CPUs
319 can be controlled through /sys/devices/system/cpu/cpu#.
320 Say N if you want to disable CPU hotplug.
327 Use the IA-PC HPET (High Precision Event Timer) to manage
328 time in preference to the PIT and RTC, if a HPET is
329 present. The HPET provides a stable time base on SMP
330 systems, unlike the TSC, but it is more expensive to access,
331 as it is off-chip. You can find the HPET spec at
332 <http://www.intel.com/hardwaredesign/hpetspec.htm>.
339 Support the ACPI PM timer for time keeping. This is slow,
340 but is useful on some chipsets without HPET on systems with more
341 than one CPU. On a single processor or single socket multi core
342 system it is normally not required.
343 When the PM timer is active 64bit vsyscalls are disabled
344 and should not be enabled (/proc/sys/kernel/vsyscall64 should
346 The kernel selects the PM timer only as a last resort, so it is
347 useful to enable just in case.
349 config HPET_EMULATE_RTC
350 bool "Provide RTC interrupt"
351 depends on HPET_TIMER && RTC=y
354 bool "K8 GART IOMMU support"
359 Support the IOMMU. Needed to run systems with more than 3GB of memory
360 properly with 32-bit PCI devices that do not support DAC (Double Address
361 Cycle). The IOMMU can be turned off at runtime with the iommu=off parameter.
362 Normally the kernel will take the right choice by itself.
363 This option includes a driver for the AMD Opteron/Athlon64 northbridge IOMMU
364 and a software emulation used on other systems.
367 # need this always enabled with GART_IOMMU for the VIA workaround
371 depends on GART_IOMMU
374 bool "Machine check support" if EMBEDDED
377 Include a machine check error handler to report hardware errors.
378 This version will require the mcelog utility to decode some
379 machine check error logs. See
380 ftp://ftp.x86-64.org/pub/linux/tools/mcelog
383 bool "Intel MCE features"
384 depends on X86_MCE && X86_LOCAL_APIC
387 Additional support for intel specific MCE features such as
391 bool "AMD MCE features"
392 depends on X86_MCE && X86_LOCAL_APIC
395 Additional support for AMD specific MCE features such as
396 the DRAM Error Threshold.
399 bool "kexec system call (EXPERIMENTAL)"
400 depends on EXPERIMENTAL
402 kexec is a system call that implements the ability to shutdown your
403 current kernel, and to start another kernel. It is like a reboot
404 but it is indepedent of the system firmware. And like a reboot
405 you can start any kernel with it, not just Linux.
407 The name comes from the similiarity to the exec system call.
409 It is an ongoing process to be certain the hardware in a machine
410 is properly shutdown, so do not be surprised if this code does not
411 initially work for you. It may help to enable device hotplugging
412 support. As of this writing the exact hardware interface is
413 strongly in flux, so no good recommendation can be made.
416 bool "kernel crash dumps (EXPERIMENTAL)"
417 depends on EXPERIMENTAL
419 Generate crash dump after being started by kexec.
421 config PHYSICAL_START
422 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
423 default "0x1000000" if CRASH_DUMP
426 This gives the physical address where the kernel is loaded. Normally
427 for regular kernels this value is 0x100000 (1MB). But in the case
428 of kexec on panic the fail safe kernel needs to run at a different
429 address than the panic-ed kernel. This option is used to set the load
430 address for kernels used to capture crash dump on being kexec'ed
431 after panic. The default value for crash dump kernels is
432 0x1000000 (16MB). This can also be set based on the "X" value as
433 specified in the "crashkernel=YM@XM" command line boot parameter
434 passed to the panic-ed kernel. Typically this parameter is set as
435 crashkernel=64M@16M. Please take a look at
436 Documentation/kdump/kdump.txt for more details about crash dumps.
438 Don't change this unless you know what you are doing.
441 bool "Enable seccomp to safely compute untrusted bytecode"
445 This kernel feature is useful for number crunching applications
446 that may need to compute untrusted bytecode during their
447 execution. By using pipes or other transports made available to
448 the process as file descriptors supporting the read/write
449 syscalls, it's possible to isolate those applications in
450 their own address space using seccomp. Once seccomp is
451 enabled via /proc/<pid>/seccomp, it cannot be disabled
452 and the task is only allowed to execute a few safe syscalls
453 defined by each seccomp mode.
455 If unsure, say Y. Only embedded should say N here.
457 source kernel/Kconfig.hz
462 # Use the generic interrupt handling code in kernel/irq/:
464 config GENERIC_HARDIRQS
468 config GENERIC_IRQ_PROBE
472 # we have no ISA slots, but we do have ISA-style DMA.
477 config GENERIC_PENDING_IRQ
479 depends on GENERIC_HARDIRQS && SMP
482 menu "Power management options"
484 source kernel/power/Kconfig
486 source "drivers/acpi/Kconfig"
488 source "arch/x86_64/kernel/cpufreq/Kconfig"
492 menu "Bus options (PCI etc.)"
497 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
504 bool "Support mmconfig PCI config space access"
505 depends on PCI && ACPI
508 bool "Unordered IO mapping access"
509 depends on EXPERIMENTAL
511 Use unordered stores to access IO memory mappings in device drivers.
512 Still very experimental. When a driver works on IA64/ppc64/pa-risc it should
513 work with this option, but it makes the drivers behave differently
514 from i386. Requires that the driver writer used memory barriers
517 source "drivers/pci/pcie/Kconfig"
519 source "drivers/pci/Kconfig"
521 source "drivers/pcmcia/Kconfig"
523 source "drivers/pci/hotplug/Kconfig"
528 menu "Executable file formats / Emulations"
530 source "fs/Kconfig.binfmt"
532 config IA32_EMULATION
533 bool "IA32 Emulation"
535 Include code to run 32-bit programs under a 64-bit kernel. You should likely
536 turn this on, unless you're 100% sure that you don't have any 32-bit programs
540 tristate "IA32 a.out support"
541 depends on IA32_EMULATION
543 Support old a.out binaries in the 32bit emulation.
547 depends on IA32_EMULATION
550 config SYSVIPC_COMPAT
552 depends on COMPAT && SYSVIPC
559 source drivers/Kconfig
561 source "drivers/firmware/Kconfig"
565 menu "Instrumentation Support"
566 depends on EXPERIMENTAL
568 source "arch/x86_64/oprofile/Kconfig"
571 bool "Kprobes (EXPERIMENTAL)"
573 Kprobes allows you to trap at almost any kernel address and
574 execute a callback function. register_kprobe() establishes
575 a probepoint and specifies the callback. Kprobes is useful
576 for kernel debugging, non-intrusive instrumentation and testing.
577 If in doubt, say "N".
580 source "arch/x86_64/Kconfig.debug"
582 source "security/Kconfig"
584 source "crypto/Kconfig"